1. Field of the Invention
The present invention relates to a transmission control device of a motorcycle. More particularly, the present invention relates to a transmission control device of a motorcycle, which detects a predetermined traveling state based on the difference in rotational speed between a front wheel and a rear wheel, and executes a shift-change control suitable for the traveling state.
2. Background of the Invention
Conventionally, there has been known a technique in which a detector for detecting a rotational speed is respectively mounted on front and rear wheels of a vehicle. A specific control is executed when a difference arises between the rotational speed of the front wheel and the rotational speed of the rear wheel.
JP-UM-A-3-2926 discloses a four-wheel drive-type four-wheeled vehicle which arranges an electromagnetic clutch between an engine and a continuously variable transmission. A control device detects when the vehicle travels on a slippery road due to the accumulation of snow or the like when a period in which the difference in rotational speed between the front wheel and the rear wheel exceeds a predetermined value is continued for a predetermined time. When such determination is performed, the control device changes over the electromagnetic clutch to a direct engagement state, even when the vehicle travels at a predetermined speed or less thus preventing a partial clutch engagement state of the electromagnetic clutch from being continued for a long time.
However, in JP-UM-A-3-2926, a technique that detects a traveling state particular to a motorcycle by detecting a difference in rotational speed between the front wheel and the rear wheel of the motorcycle and changes over a shift-change control of an automatic transmission to a different state from a normal state has not been studied.